diff --git a/src/Fl_Window_Driver.cxx b/src/Fl_Window_Driver.cxx
index d781fcedb..65ccae8b8 100644
--- a/src/Fl_Window_Driver.cxx
+++ b/src/Fl_Window_Driver.cxx
@@ -87,7 +87,7 @@ void Fl_Window_Driver::draw() { pWindow->draw(); }
 void Fl_Window_Driver::make_current() { }
 
 /**
- Make the window visble and raise it to the top.
+ Make the window visible and raise it to the top.
  */
 void Fl_Window_Driver::show() { }
 
diff --git a/test/unittest_about.cxx b/test/unittest_about.cxx
index 3c4084d31..4555643e4 100644
--- a/test/unittest_about.cxx
+++ b/test/unittest_about.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -32,7 +32,7 @@ public:
 "The Unit Testing application can be used to verify correct graphics rendering "
 "on the current platform. The core developer team uses this program to make sure that the "
 "FLTK user experience is identical on all supported graphics systems."
-"<h3>the UI Designer</h3>\n"
+"<h3>The UI Designer</h3>\n"
 "<p>Designing a good user interface is an art. Widgets must be selected and carefully positioned "
 "to create a consistent look and feel for the user. Text must fit into given boxes and graphic "
 "elements must be correctly aligned. A good UI library will give consistent results on any "
@@ -40,7 +40,7 @@ public:
 "<p>FLTK supports a large collection of platforms and graphics drivers. This unit testing "
 "application contains modules which will test rendering and alignment for most "
 "FLTK core graphics functions.</p>\n"
-"<h3>the Developer</h3>\n"
+"<h3>The Developer</h3>\n"
 "<p>Unittest is also a great help when implementing new graphics drivers. The tests are sorted "
 "in the same order in which a new graphics driver could be implemented. Most tests rely "
 "on the previous test to function correctly, so sticking to the given order is a good idea.</p>\n"
diff --git a/test/unittest_circles.cxx b/test/unittest_circles.cxx
index 0d3fad25d..9f919be60 100644
--- a/test/unittest_circles.cxx
+++ b/test/unittest_circles.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_complex_shapes.cxx b/test/unittest_complex_shapes.cxx
index 399243e4b..ce8f30c6f 100644
--- a/test/unittest_complex_shapes.cxx
+++ b/test/unittest_complex_shapes.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_fast_shapes.cxx b/test/unittest_fast_shapes.cxx
index c486eb147..644384f22 100644
--- a/test/unittest_fast_shapes.cxx
+++ b/test/unittest_fast_shapes.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_images.cxx b/test/unittest_images.cxx
index dcc720f1b..3f2a6ef25 100644
--- a/test/unittest_images.cxx
+++ b/test/unittest_images.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2016 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_points.cxx b/test/unittest_points.cxx
index 22291b2ca..cf116477d 100644
--- a/test/unittest_points.cxx
+++ b/test/unittest_points.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -188,7 +188,7 @@ public:
                // Description:
                "This draws a black frame around a white square.\n\n"
                // Things to look out for:
-               "If red pixels are visble or black pixels are missing, graphics clipping is misaligned."
+               "If red pixels are visible or black pixels are missing, graphics clipping is misaligned."
                );
 
     a+=100;
@@ -235,7 +235,7 @@ public:
                // Description:
                "This draws a black frame around a white square. The square is slightly smaller.\n\n"
                // Things to look out for:
-               "If red pixels are visble or black pixels are missing, graphics clipping is misaligned."
+               "If red pixels are visible or black pixels are missing, graphics clipping is misaligned."
                );
 
     gl_test_win = new GLTestWin(a+24+8, b+9-5, 10, 4*24+2*16);
diff --git a/test/unittest_schemes.cxx b/test/unittest_schemes.cxx
index 767a18bfc..275950755 100644
--- a/test/unittest_schemes.cxx
+++ b/test/unittest_schemes.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2017 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // Nods to Edmanuel Torres for the widget layout (STR#2672)
 //
diff --git a/test/unittest_scrollbarsize.cxx b/test/unittest_scrollbarsize.cxx
index 10b5668a2..9ecdf73fe 100644
--- a/test/unittest_scrollbarsize.cxx
+++ b/test/unittest_scrollbarsize.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_simple_terminal.cxx b/test/unittest_simple_terminal.cxx
index 778319028..06c376fe9 100644
--- a/test/unittest_simple_terminal.cxx
+++ b/test/unittest_simple_terminal.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2017 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_symbol.cxx b/test/unittest_symbol.cxx
index 9e922394e..e45b62317 100644
--- a/test/unittest_symbol.cxx
+++ b/test/unittest_symbol.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittest_text.cxx b/test/unittest_text.cxx
index 9613d54a8..67c46f397 100644
--- a/test/unittest_text.cxx
+++ b/test/unittest_text.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
@@ -72,7 +72,7 @@ public:
       fl_color(FL_GREEN); fl_draw("fl_text_extents bounding box in GREEN", xx, yy);
       fl_color(FL_BLACK);
       xx = x0 + 10;  yy += 30;
-      fl_draw("NOTE: On systems with text anti-aliasing (e.g. OSX Quartz)", xx, yy);
+      fl_draw("NOTE: On systems with text anti-aliasing (e.g. macOS Quartz)", xx, yy);
       w0 = h0 = 0; fl_measure("NOTE: ", w0, h0, 0);
       xx += w0; yy += h0;
       fl_draw("text may leak slightly outside the fl_text_extents()", xx, yy);
diff --git a/test/unittest_viewport.cxx b/test/unittest_viewport.cxx
index 0ae98fac5..417a9cfa5 100644
--- a/test/unittest_viewport.cxx
+++ b/test/unittest_viewport.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2010 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this
diff --git a/test/unittests.cxx b/test/unittests.cxx
index 47261241c..a4e231f06 100644
--- a/test/unittests.cxx
+++ b/test/unittests.cxx
@@ -1,7 +1,7 @@
 //
 // Unit tests for the Fast Light Tool Kit (FLTK).
 //
-// Copyright 1998-2021 by Bill Spitzak and others.
+// Copyright 1998-2022 by Bill Spitzak and others.
 //
 // This library is free software. Distribution and use rights are outlined in
 // the file "COPYING" which should have been included with this file.  If this